1. Field of the Invention
The present invention relates to a burner for the combustion of a liquid and/or gaseous fuel. More particularly, the present invention relates to the ignition of fuel in a premix type burner to provide better flame propagation and a more stable flame front.
2. Discussion of Background
In any burner for a firing system or internal combustion engine or combustion chamber of a gas turbine group, it is repeatedly found that an excessive air or mixture velocity is intrinsically always present at the ignition electrodes. Particularly in the case of premixed burners, i.e. in the case of burners in which the premixing zone is an integrated constituent part of the burner itself, such as is disclosed in EP-A1-0 321 809, it is necessary to ensure that the ignition of the fuel/air mixture takes place or proceeds at a location where there is no excessive flow velocity of the medium; at the same time it is also necessary to ensure that the propagation of the flame front or flame tongues in the direction of the outlet from the burner, where a reverse flow zone is established, takes place in a defined manner. It is also, of course, necessary to ensure that ignition takes place at a location where there is an ignitable stoichiometric, or preferably slightly sub-stoichiometric, mixture and where the initial flame formation can also be maintained until the flame front has reached said stabilization location at the outlet from the burner. As far as can be seen, particularly with respect to premixed burners of the type already mentioned, such a configuration which can satisfy the conditions postulated and can obviate the disadvantages with respect to the ignition, has not yet been proposed.